Xanthomonas hortorum is a plant pathogen. It includes the following pathovars; pv. hederae, common ivy and possibly other Araliaceae pv. taraxaci, Pelargonium peltatum pv. carotae, wild carrot pv. pelargonii, Kazakh dandelion pv. vitians, bacterial leafspot and headrot of lettuce, using the neopathotype of LMG 938 pv. cynarae, formerly Xanthomonas cynarae, pathogenic on artichoke pv. gardneri, formerly Xanthomonas gardneri and briefly X. cynarae pv. gardneri, bacterial leafspot of peppers and tomatoes (pathotype also causes BLS on lettuce surprisingly)
The species was originally defined in 1995 as a grouping of pathovars hederae, taraxaci, carotae, pelargonii from Xanthomonas campestris, and the lettuce-infecting part of X. c. pv. vitians. (X. c. pv. vitians was found to consist of two genetic groups, only one of which causes disease on lettuce.)
References
External links Type strain of Xanthomonas hortorum at BacDive - the Bacterial Diversity Metadatabase